Refrigerating apparatus

ABSTRACT

The invention provides refrigerating apparatus ( 10;100 ) for chilling an object ( 26 ), the refrigerating apparatus ( 10;100 ) comprising a chamber ( 12;112 ) having a longitudinal axis ( 18;118 ), an inlet ( 22;122 ) and an outlet ( 24;124 ) spaced along the longitudinal axis ( 18;118 ), the refrigerating apparatus ( 10;100 ) further comprising means for generating a fluid flow, characterised in that notation means ( 128 ) are provided for causing the fluid flow to follow a helical path about the longitudinal axis ( 18;118 ) within the chamber ( 12;112 ) between the inlet ( 22;122 ) and the outlet ( 24;124 ).

The invention relates to refrigerating apparatus. The invention relatesparticularly, but not exclusively, to refrigerating apparatus suitablefor chilling objects rapidly. The invention further relates to a methodof refrigeration.

Conventional refrigerating apparatus comprises means for generating andmaintaining a low temperature environment in which to store food orbeverages. However, it is often desirable to chill an object, forexample, a bottle of wine or beer, quickly. This is not readilyachievable by leaving the bottle in a refrigerator as it takes aconsiderable time before the contents of the bottle are chilled to thedesired temperature. Often, in order to speed up the chilling process,the consumer places the bottle in a freezer. However, this method hasthe disadvantage that it is not easily controllable and it relies on theconsumer remembering to take the bottle out of the freezer before thecontents freeze. An example of an apparatus for chilling an object morequickly is shown in U.S. Pat. No. 4,358,932 which describes a system ofintroducing cold air, taken directly from the freezer compartment of arefrigerator, to a chamber containing a bottle. The cold air enters thechamber at the base and flows upwardly, in the direction of thelongitudinal axis of the chamber. As the cold air passes the bottle,heat is transferred from the bottle and its contents to the cold air,thereby causing the temperature of the contents to fall. However, theamount of time taken to chill the contents may still be unsuitably longfor the consumer's needs. For example, following the calculation givenin U.S. Pat. No. 4,358,932, a 1 litre bottle would take 23 minutes tochill to from 75° F. to 35° F.

The type of arrangement shown in the prior art has the disadvantage thatonly a small area of the bottle is in direct contact with the cold airand the residency time of the cold air passing the bottle is short.Therefore, heat transfer from the bottle and its contents to the coldair is not maximised. Additionally, the air flow through the chamber isnot particularly turbulent and so heat exchange is relativelyinefficient.

It is an object of the present invention to provide a refrigeratingapparatus suitable for chilling objects rapidly.

The invention provides refrigerating apparatus for chilling an object,the refrigerating apparatus forming part of a refrigerator andcomprising a chamber having a longitudinal axis, an inlet and an outletspaced along the longitudinal axis, the refrigerating apparatus furthercomprising means for generating a fluid flow, characterised in thatrotation means are provided for causing the fluid flow to follow ahelical path about the longitudinal axis within the chamber between theinlet and the outlet. In this configuration, there is an increase in thecontact time between the fluid flow and the object. Therefore, heattransfer is more efficient which leads to a reduction in the time takento chill the object.

Preferably the inlet is arranged tangential to the chamber so as tocause the fluid flow to follow a helical path about the longitudinalaxis within the chamber. Provision of the tangential inlet ensureshelical fluid about the object which maximises the contact time duringwhich heat transfer occurs.

Preferably a support is provided for supporting the object spaced from awall of the chamber. The support ensures that the object is placed inthe chamber in an optimum position for heat transfer.

In a preferred embodiment, the apparatus comprises a plurality ofchambers, each chamber being dimensioned so as to house an object to bechilled. It is an advantage to be able to chill a number of objectssimultaneously. This is particularly suitable for use in, for example,restaurants where it is desirable to have a large number of alternativebeverages available on demand.

The invention further provides a method of chilling an object in arefrigerator, comprising the steps of:

-   -   a) placing an object to be chilled in a chamber in the        refrigerator, the chamber having a longitudinal axis, an inlet        and an outlet spaced along the longitudinal axis;    -   b) introducing a fluid flow to the inlet of the chamber;    -   c) causing the fluid flow to follow a helical path about the        longitudinal axis and around the object to be chilled;        and    -   d) allowing the fluid flow to exit the chamber via the outlet.

Embodiments of the invention will now be described, by way of exampleonly, with reference to the accompanying drawings, wherein:

FIG. 1 is a schematic view of a first embodiment of refrigeratingapparatus according to the invention, the embodiment being illustratedhere with a wine bottle housed therein;

FIG. 2 is a schematic view of a second embodiment of refrigeratingapparatus according to the invention;

FIG. 3 is a schematic view of the apparatus of FIG. 1 in combinationwith other elements; and

FIG. 4 is a schematic view of a third embodiment of refrigeratingapparatus according to the invention.

FIG. 1 shows a first embodiment of refrigerating apparatus 10 accordingto the invention. The refrigerating apparatus 10 comprises a chamber 12having first end wall 14, a second end wall 16 and a cylindrical wall 20extending therebetween. The chamber 12 is thus generally cylindrical andhas a longitudinal axis 18. It will be appreciated that the chamber canbe of any shape suitable for receiving and housing an object to bechilled. An inlet 22 for introducing a chilled fluid flow to the chamber12 is provided at a first end 12 a thereof adjacent the first end wall14. The inlet 22 is circular in cross-section and communicatestangentially with the chamber 14. An outlet 24 for carrying the fluidflow out of the chamber 12 is provided at a second end 12 b thereofadjacent the second end wall 16. The outlet 24 is circular incross-section and communicates tangentially with the chamber 12. Theinlet 22 and the outlet 24 are spaced apart along the axis 18.

FIG. 1 shows a wine bottle 26 housed in the cylindrical chamber 12 butit will be understood that the wine bottle 26 may be replaced with anysuitable object that the consumer wishes to chill. Equally, the chamber12 may be shaped and dimensioned so that other objects may beconveniently received and stored therein. A stand 28 is provided on thesecond end wall 16 to allow the object (here the wine bottle 26) to besupported. The stand 28 is located and arranged so that, when the winebottle 26 is supported thereon, it is located substantially centrally ofthe chamber 12. The stand 28 has a platform 30 and a plurality of legs32 which ensure that the platform 30 is spaced from the second end wall16. Hence, a gap is provided between the second end wall 16 and theplatform 30 on which the wine bottle 26 is supported.

The refrigerating apparatus 10 shown in FIG. 1 operates in the followingmanner. A chilled fluid flow, preferably air, is introduced into thefirst end 12 a of the chamber 12 via the inlet 22. The tangentialarrangement of the inlet 22 with respect to the chamber 12 causes theincoming chilled fluid to follow a generally helical path around thecylindrical wall 20 whilst it moves along the axis 18 in the directionof the outlet 24. A simplified version of the path followed by the fluidis shown in FIG. 1. The helical path followed by the fluid isconsiderably longer than a direct path between the inlet 22 and theoutlet 24. Furthermore, by forcing the fluid to follow a helical path,the turbulence created in the fluid flow improves the transfer of heataway from the object 26 to be cooled.

The fluid flow exits the chamber 12 via the outlet 24 which communicateswith the second end 12 b of the chamber 12. The fact that the platform30 is spaced apart from the second end wall 16 means that the fluid flowcan pass underneath the platform 30 before it exits the chamber 12. Thefluid flow is therefore able to cool the stand 28 by transferring heatenergy away from it. This is particularly effective if the stand 28 ismade from a thermally conductive material, eg. metal. If the stand 28 iscooled, this can also assist with the cooling of the object 26.

A second embodiment of the invention is shown in FIG. 2. This embodimentdiffers from the first embodiment in that the refrigerating apparatus100 comprises an inlet 122 and an outlet 124 which are coincident withthe longitudinal axis 118 of the chamber 112. Further, a fan assembly128 is provided at the first end 114 adjacent the inlet 122. The fanassembly 128 is illustrated in FIG. 2 as lying generally on thelongitudinal axis 118 but the position of the fan assembly 128 may bealtered so as to cause the incoming fluid flow to follow a helical pathdown the chamber 112. The method of use of the apparatus shown in FIG. 2is essentially the same as that of FIG. 1. A chilled fluid flow entersthe chamber 112 via the axial inlet 122. The fan assembly 128 is causedto rotate so as to force the incoming fluid flow to travel along agenerally helical and somewhat turbulent path about the longitudinalaxis 118 of the chamber 112. It will be appreciated that alternativemeans of causing the incoming axial fluid flow to follow a helical pathcould replace the fan assembly 128. For example, fixed vanes could beemployed to create the same effect. What is important is that theincoming fluid flow is forced to follow a generally helical andturbulent path within the chamber 112.

FIG. 3 illustrates the apparatus shown in FIG. 1 and described above incombination with other elements. The apparatus 10 is connected via theinlet 22 and the outlet 24, in combination with further pipe work, to achamber 140. An evaporator 150 is located inside the chamber 140, alongwith a fan assembly 152. Preferably, the pipe work connecting theapparatus 10 to the chamber 140 is thermally lagged, as is the chamber140. In use, liquid refrigerant (for example, butane orhydrofluoroalkane) is pumped at low pressure into the evaporator 150 viaan inlet 154. The low pressure of the liquid refrigerant causes it toevaporate into a gas. The change in the physical state of therefrigerant causes an exothermic reaction whereby heat is lost from theliquid and the liquid rapidly cools causing the temperature in theevaporator 150 to drop. The fan assembly 152 generates a flow of airwhich passes across the evaporator 150 and becomes chilled. It is thenpassed towards the chamber 12 (the direction of flow is shown by arrowsA in FIG. 3). The chilled air enters the chamber 12 via the inlet 22 andis caused to follow a helical path 160 around the object to be chilled,passing from the first end 12 a of the chamber 12 towards the second end12 b. The contact time between the object and the chilled air is greatlyincreased because of the helical nature of the flow. In this way, heattransfer from the object to the chilled air is maximised and the objectrapidly losses heat and cools down.

The air exiting the chamber 12 via the outlet 24 is at a highertemperature than the chilled air entering at the inlet 22 because of theheat transfer process. However, the exiting air can be circulated backto the evaporator 150 for rechilling. The heat generated by the processis exchanged within the evaporator where it can be removed from thesystem by means of a conventional compressor and condenser system. Itwill be appreciated that the apparatus illustrated in FIG. 2 can replacethe apparatus 10 used in the system shown in FIG. 3.

FIG. 4 shows a third embodiment of the invention. The refrigeratingapparatus 200 comprises an arrangement of chambers 212 each having thesame configuration as the chamber 12 of FIG. 1. It will be appreciatedthat the chambers 212 could alternatively have the configuration of thatshown in FIG. 2. Each chamber 212 has a tangential inlet 222 and atangential outlet 224. At least one main inlet 226 (two are shown here)feeds chilled air into the refrigerating apparatus 200 and a proportionof the chilled air is directed into each inlet 222. The chilled airfollows a helical path downwardly through each chamber 212 beforeexiting via the respective outlet 224 as previously described. Theexiting air is carried away via one or more main outlets 228. The numberand arrangement of chambers 212 is not limited to that shown in thefigure. This arrangement is beneficial when a number of objects requireto be chilled simultaneously.

The invention is not intended to be limited to the precise features ofthe embodiments described above. Other variations and modifications willbe apparent to a skilled reader. For example, as has been mentioned, thechamber may be of any suitable shape to hold the object to be chilled.Also, the fluid used to chill the object need not be air but could beany suitable fluid. In some circumstances, the fluid could be a liquid,eg. water.

1. A refrigerating apparatus for chilling an object, the refrigeratingapparatus forming part of a refrigerator and comprising a chamber havinga longitudinal axis, an inlet and an outlet spaced along thelongitudinal axis, a device for generating a fluid flow within thechamber and a structure for causing the fluid flow to follow a helicalpath about the longitudinal axis within the chamber between the inletand the outlet.
 2. A refrigerating apparatus as claimed in claim 1,wherein the inlet is arranged tangential to the chamber so as to causethe fluid flow to follow a helical path about the longitudinal axiswithin the chamber.
 3. A refrigerating apparatus as claimed in claim 1or 2, wherein the outlet is arranged tangential to the chamber.
 4. Arefrigerating apparatus as claimed in claim 1 or 2, wherein the chamberis cylindrical.
 5. A refrigerating apparatus as claimed in claim 1 or 2,wherein the longitudinal axis of the chamber is substantially vertical.6. A refrigerating apparatus as claimed in claim 1 or 2, wherein theinlet and the outlet are at opposite ends of the chamber.
 7. Arefrigerating apparatus as claimed in claim 1 or 2, wherein the fluidflow is a chilled airflow.
 8. A refrigerating apparatus as claimed inclaim 1 or 2, wherein the means device for generating the fluid flowcomprises a fan and an evaporator, the evaporator housing a refrigerant.9. A refrigerating apparatus as claimed in claim 8, wherein the outletis arranged so as to pass the fluid flow to the evaporator forrecirculation.
 10. A refrigerating apparatus as claimed in claim 1 or 2,wherein a support is provided for supporting the object spaced from awall of the chamber.
 11. A refrigerating apparatus as claimed in claim 1or 2, wherein the chamber is dimensioned so as to hold a beveragebottle.
 12. A refrigerating apparatus as claimed in claim 1 or 2,wherein the apparatus comprises a plurality of chambers, each chamberbeing dimensioned so as to house an object to be chilled.
 13. (canceled)14. A method of chilling an object in a refrigerator, comprising: a)placing an object to be chilled in a chamber in the refrigerator, thechamber having a longitudinal axis, an inlet and an outlet spaced alongthe longitudinal axis; b) introducing a fluid flow to the inlet of thechamber; c) causing the fluid flow to follow a helical path about thelongitudinal axis and around the object to be chilled; and d) allowingthe fluid flow to exit the chamber via the outlet.
 15. A method ofchilling an object as claimed in claim 14, wherein the fluid flow isintroduced tangentially to the chamber.
 16. A method of chilling anobject as claimed in claim in claim 14 or 15, wherein the fluid flowpasses at least twice around the object before being allowed to exit thechamber.
 17. A method of chilling an object as claimed in claim 14 or15, wherein the fluid flow is caused to flow between a wall of thechamber and a support on which the object is placed.
 18. A method ofchilling an object as claimed in claim 14 or 15, further comprisingchilling the fluid flow prior to entry into the chamber.
 19. A method ofchilling an object as claimed in claim 18, further comprising passingthe fluid flow through an evaporator.
 20. A method of chilling an objectas claimed in claim 19, further comprising returning the fluid flow tothe evaporator for rechilling after exiting the chamber via the outlet.21. A method of chilling an object as claimed in claim 20, wherein therechilled fluid flow is introduced to the inlet of the chamber. 22.(canceled)